Answering Your Most Common Questions About Sign Languages

Sign language scuplture “Life is beautiful, be happy and love each other!” by Zuzana Čížková at Kobrova Bus Stop in Holečkova Street in Prague. Photo by ŠJů, Wikimedia Commons.

How many sign languages are there in the world?

It’s difficult to obtain an accurate number of languages in the world for a variety of reasons — this becomes all the more difficult when trying to put a number on signed languages specifically. Ethnologue lists 142, but there are many more than that; for example, Rwandan Sign Language is not listed in the Ethnologue, although it’s an established language within the country. Wikipedia estimates the number to be around 300.

Signing communities are often small and, in some parts of the world, extremely discriminated against. Education systems often do not teach sign languages and will even go so far as to prohibit the use of sign languages within schools. Jessica Lee writes in her dissertation on the Deaf community of Tanzania that although there is one standardized sign language of Tanzania, Tanzanian Sign Language (LAT), there are hundreds of home signs that have emerged around the country (home signs are communication systems developed usually by Deaf children who are isolated from the Deaf community).

This creates a challenge for linguists working to classify and document sign languages. In spoken languages, there is confusion and ongoing discussions revolving around the classification of languages and dialects; similarly, this occurs in signed languages — sign languages commonly develop from home signs and village sign languages, when children who are deaf or hard of hearing attend school and merge their signs together. Overtime, this develops into a full fledged language.

Around 5% of the world’s population is hard of hearing or deaf, totaling to around 360 million people. Yet sign languages are considered minority languages, making them, and the people who use them, subject to the perceptions that come with being a minority.

Further, there are not many people who study sign language linguistics or people who are trained in sign language documentation. Pairing all these factors with an overall lack of knowledge regarding the study of sign languages, this makes it challenging for documentation and data collection.

Why isn’t there just one universal sign language then to make it easier for documentation and communication?

Primarily for the same reason as to why there isn’t a universal spoken language: language and culture are intertwined. Language can be viewed as a communicative expression of culture; when you interact with a language, you are interacting with the culture that uses that language. A great example of this from sign languages is the missionization of Finnish Sign Language (FSL) in Eritrea. In FSL, the sign DOG is visualized with two pats on the upper right leg, a “come hither” type of approach, since dogs are kept as pets in Finland. In Eritrea, where FSL was taught and implemented for decades due to missionaries, this sign does not make sense culturally, as dogs are usually considered wild and unsafe. A couple of decades ago, the Eritrean Deaf community started to work together to create more localized signs that were appropriate to their culture (including the changing of the sign DOG).

There are lingua francas that people can use to communicate cross-culturally, usually English in spoken languages and International Sign in signed languages. International Sign (IS) is a contact variety of sign languages, with a limited lexicon and an extensive dependency on role playing.

Even if we did create a universal sign language, or a universal spoken language, and we then managed to teach it to everyone and convince everyone to regularly utilize it, we would find that that language quickly would shift. Almost overnight we would have different dialects and different slang words being created, until, we find ourselves once again with different languages around the world. Language changes, and will constantly do so.

Do sign languages use the grammar of the local spoken language?

Always there is a common misconception that sign languages are somehow dependent on spoken languages: that they are spoken language expressed in signs, or that they were invented by people who are hearing. Sign languages, just like all natural languages, are developed by the people who use them. American Sign Language (ASL) shares more syntax with spoken Japanese than it does with English. ASL is not related to British Sign Language (BSL), as English speakers might assume, but is derived from French Sign Language (LSF).

Sometimes, sign languages borrow from spoken languages around them, but this is due to languages being in contact with each other — a phenomenon which occurs in languages all around the world — not because spoken languages are better or more complex than signed languages.

How are sign languages related to each other? Are some branches more closely related?

The classification system for sign languages of the world is extremely outdated: it was put together in 1991, by Henri Wittmann. He based it on the Ethnologue edition at the time (1988) which listed 69 sign languages. Eleven more languages were added by Wittmann. Wikipedia has a simplified list of language families, which is reflective of the state of knowledge we have today in sign language linguistics. The largest sign languages family is the

Within the LSF family, there are many clusters, including the influential American Sign Language cluster. This is a subset of the LSF family and includes sign languages that have been heavily affected by ASL. Many African sign languages fall under this cluster, due to the spread of ASL by the missionary Andrew Foster. Some classify Bolivian Sign Language as a dialect of ASL. Thai Sign Language is derived from ASL and the native sign languages of Bangkok and Chiang Mai.

There are also sign language isolates (meaning they aren’t related to any other language), such as Nicaraguan Sign Language, Turkish Sign Language, Kata Kolok (video on our YouTube), Al-Sayyid Bedouin Sign Language, and Providence Island Sign Language.

Are certain sign languages mutually intelligible?

Yes, depending on factors similar to spoken languages (region, colonial influence, population size, standardization, etc). The Danish Sign Language family is a subgroup of the French Sign Language family mentioned above and is comprised of Norwegian Sign Language, Icelandic Sign Language (ICL), and of course, Danish Sign Language (DTS). They are different languages, but have a high degree of similarity. Aldersson analyzed ICL and DTS and found that 37% of signs were different in structure, 16% were similar, and the rest were the same.

Are there some international signs that mean the same thing in different languages?

Not entirely —although sign languages are more similar in form than spoken languages due to iconicity, uniformity in spatial syntax, and the ability of the users to exploit gesture when conversing with a signer of another language. Needless to say, this is extremely under-researched and further lexical comparisons across sign languages need to be conducted before fully answering this.

Anecdotally though, even different signs for “hello” can be found across sign languages. For example, in Kenyan Sign Language (KSL), the sign HELLO would be interpreted by a native English speaker as more of a salute as opposed to a general “hello”. But due to the fact that a wave to say hello is quite universal, this is easy to jump across.

Names of countries are often different, but recently there are been acknowledgement of European sign languages articulating country names in the same manner. AMERICA is often signed by interlacing fingers and stirring a pot (symbolic of a melting pot). Although this website equates sign languages with national flags (and countries can have more than one sign language, so this is not representative), you can watch videos on this website to compare signs words in various languages.

Due to the visual-spatial nature of signed languages and the high degree of iconicity, accompanied by Deaf people’s knowledge of navigating linguistic barriers due to living in a Hearing-centric world, if two Deaf people who know different languages meet, they are able to come to a mutual understanding and learn to communicate together in a relatively short amount of time — especially compared to two people who are hearing working to accomplish the same (which, in the latter case, they would often resort to employing gestural communication).

How do children learn sign languages?

They are taught naturally, just like any other languages. And just like children learning spoken languages, there are sign language milestones and baby babble. When babies are learning to sign, they “babble” with their hands as they learn to develop more dexterity to articulate their signs.

Is there an equivalent to speech impediments, like if a signer’s fingers can’t move a certain way?

Yes, there definitely are equivalents. Stuttering is actually a neurological disorder, so it affects everyone equally — Deaf or Hearing. Someone who is deaf and has a speech disorder might repeat the first motion of a sign involuntarily, for instance.

There are a lot of signers who have stiff fingers due to injuries, arthritis, etc. and they might have trouble with certain signs or with signing at a rapid pace. Oftentimes these people are teased (lovingly, so I’ve been told!) by their friends/family for having a “lisp”.

How are different signs distinguished?

I’ll try to be as concise as possible when answering this, but the grammar of sign languages is very intricate and complex! To discuss the distinguishing factors of sign languages, we need to analyze signs in terms of their parameters. Parameters are similar to phonemes in spoken languages. A phoneme is a perpetually distinctive sound that distinguishes one word from another: dad vs bad, love vs dove, crate vs crave, and so on. These miniscule units are used to study spoken languages and how each sound works together and influences each other.

In sign languages, parameters are the smallest contrastive unit of of study available and they include handshape, movement, location, palm orientation, and non-manual markers (i.e. eyebrow raising). These parameters all work together to give individual meaning to signs. Signs can share one of more of the same parameters: for instance, the ASL the sign SCHOOL only differs from the sign IMPOSSIBLE by one parameter (the handshape).

Each sign language employs different parameters and each parameter is compromised of a number of different primes, changing a prime can alter the meaning of the sign or can render it meaningless. For instance, the handshape parameter could have 30 (or more) varieties in a certain language; handshape primes include A, B, M, 5, and so on. In each group of primes, there is more variation based on similar handshapes, effectively creating what we term in spoken languages as allophones. Just as /z/ in English carries the features [-nasal, +sibilant,+voice], plus many others, handshapes can be classified using features such as [± compact, ± spread, ± broad], and so on. Handshape is the hardest parameter to acquire and leads to inter- and intra-signer variations. All known sign languages share a number of handshape variations; there are some more complex handshapes which can be found only in a few sign languages. Sign languages also vary in the size of their handshape inventory, just as spoken languages vary in their vowels and consonants.

The second parameter, movement, is how the hand (or hands, depending on the sign) move. Movement can be classified as upward, downward, forward, wave, zigzag, diagonal, supinating rotation, etc. This category can be further broken down into two sub-sections: hand-internal movements and path movements. An hand-internal movement is when the movement occurs strictly through movement of the fingers. In constrast, path movements are where the handshape remains the same and the hand moves as a whole throughout the sign articulation. Within the movement parameter, discrepancy is less widely available, as the differences are much more apparent.

The location parameter relates to where the hand(s) is/are located in relation to the signers’ body. Locations are usually coded as either neutral, face, head, mouth, neck, chest, or sides. This parameter is not independent — it is integrated into the sign. Palm orientation is equally straightforward: palms can either be turned upward, downward, facing towards the signer, away from the signer, etc.

The final parameter is the non-manual signal, or marker. Non-manual signals are grammatical and semantic features that are not shown with the hands. These signals include various facial expressions, eyebrow raising, mouthing, body shifting, head tilting, etc. that can accompany signs. This parameter is used to modify verbs, adjectives, and other adverbs. Some signs require these signals to be produced correctly, some can be added by the speaker to show their emotions at the time or to show their personality. The resources of the visual-gestural modality appear to allow more frequent iconicity in sign language lexicons in comparison to spoken languages (mentioned above). Every sign language has a different relationship to non-manual markers and implements them to different varying degrees.

Two-handed signs can be further broken down based on the role each hand has: either (i) both hands move: they generally have the same handshape and the movement can either be copying and simultaneous, an opposite movement, or changing movement — when the hands produce the same movement, but in different directions passing across each other; (ii) the dominant hand moves — this changes depending on whether the person is right- or left-handed — the non-dominant hand stays in place, and both hands have same handshape; or, (iii) the dominant hand moves while the non-dominant hand remains in place, but the hands have different handshapes in this configuration.

There’s a lot more to be said on this, especially when explaining verbs and how they are created, but we can dive into that later on!

Comment below if you have any further questions you would like answered!


Kristen Tcherneshoff

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I should separate my work and personal Medium account at some point. Until then, here’s a strange combination of linguistics, activism, & all my life stories.


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